[010628]
To reproduce:
1. Convert filesystem into webmodule
2. Add some jar into WEB-INF/lib (not mandatory)
3. Create JSP in webmodule
4. Add this JSP to project (Tools | Add to Project)
5. Unmount webmodule
6. Click on filesystem node in explorer and select Customize from popup menu.
Look what is happening.
Now WEB-INF/classes and jars from WEB-IN/lib are repeatedly mounted and some are
umnounted in infinitive loop, number of mounted filesystem increases and IDE
loads 100% CPU. After a while tens of new filesystems are mounted.